(Ed. note: The following is by Adam Albrec, author of PPC Media Center, cross-posted here from various other places. It's about SSDs, and since there's virtually nothing on this blog about SSDs on PowerPC Macs, I thought I'd include it here with his permission.)
I just got an OWC 'TRIM-Free' ssd for my MDD DP 1.42. At first, this was easily the best performance I've EVER had on this machine - OS9 level peppiness even running Tiger with heavy apps like TenFourFox. Opened 2 9000x6000 pixel images in Photoshop and doubled them by 10% increments, then opened TenFourFox with 50+ tabs - could move between PS History-states and then back over to TenFourFox and cycle tabs with no-more than 1/10th second delay!!!! Was ROCKIN' 11GB of Virtual Memory!
BUT it all came crashing down in less than a day.
The drive became completely unresponsive and I could not get any further than boot. Thought: "Knew this was too-good to be true!" Well OWC tested the drive and reported back it was fine!?!?!? To be on safe-side they sent another knew one and adviced me to attach to newer machine (Linux in my case) and verify it had newest firmware before using. Well this meant having to partition to MBR so Linux could see it. Well, once it was verified, I repartitioned back to APT to put in the Mac, but suddenly it was unresponsive again like the 1st one! Well to use the parlance of our time - WTF?
So it was time to get me some edumacation into this stuff. The reason Sandforce controllers don't need TRIM is that they do it themselves when the drive is idle. On a modern system, with copious amounts of RAM, the only time the 'Garbage Collection' function is noticeable, is when large numbers of blocks are being reclaimed. In older OSX systems with 2GB RAM limits, this becomes much more likely than in newer systems.
So what to do? In this case, the drive was 120GB (for $64 = Good Deal), I had initially partitioned it into 2 sections (80GB for OSX and 40GB for OS9). On a light day, maybe this would be fine, but on those 'Heavy-Flow Days', I can easily push 20GB or so onto VM, so I either plan on allowing for periodic down-time or give the drive all the room it can support to enable maximum paging flexibility. The second idea has been great and no more problems. Also, some have said that with Sandforce's drives this also makes sense in wear-leveling, because the more of the drive is available, the more it can spread the data around, and the drives also auto-recopy data periodically to make sure it stays fresh.
Boot-times/program load times aside, one of these SSDs are the best investment you can put into your classic PowerMac. Like having virtually limitless RAM. But you need to allow it more openspace to auto-maintain (for G4/32-bit systems at least 40GB).
Also while they do still offer the 'Legacy' IDE/ATA versions, there is no reason to pay the extra $40 when an IDE/Sata adaptor (at least if you are on a desktop with the room inside) like this one http://www.ebay.com/itm/Pata-IDE-To-Sata-Hard-Drive-Adapter-Converter-3-5-HDD-DVD-Parallel-to-Serial-ATA-/171424564491 is available for about $6 and works like a charm.
Happy PPC Computing Folks!!
•• Note on IDE/SATA adaptors: The smaller inline ones like mentioned above, generally have a 2TB limit. Larger drives often require a PCI card. Also, they sometimes add an additional 1-second delay to Access/Spin-Up times. Once data starts moving, there is no delay, but if your only drive is an SSD, it might make sense to experiment disabling 'disksleep' on pmset in Terminal. Even in this case, however, there will occasionally be a momentary searching during bootup for the system folder as the card comes to life. This is normal.